---
stage: Create
group: Source Code
info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/product/ux/technical-writing/#assignments
---

# AsciiDoc **(FREE)**

GitLab uses the [Asciidoctor](https://asciidoctor.org) gem to convert AsciiDoc content to HTML5.
Consult the [Asciidoctor User Manual](https://asciidoctor.org/docs/user-manual/) for a complete Asciidoctor reference.

You can use AsciiDoc in the following areas:

- Wiki pages
- AsciiDoc documents (`.adoc` or `.asciidoc`) inside repositories

## Syntax

Here's a brief reference of the most commonly used AsciiDoc syntax.
You can find the full documentation for the AsciiDoc syntax at <https://asciidoctor.org/docs/>.

### Paragraphs

```plaintext
A normal paragraph.
Line breaks are not preserved.
```

Line comments, which are lines that start with `//`, are skipped:

```plaintext
// this is a comment
```

A blank line separates paragraphs.

A paragraph with the `[%hardbreaks]` option preserves line breaks:

```plaintext
[%hardbreaks]
This paragraph carries the `hardbreaks` option.
Notice how line breaks are now preserved.
```

An indented (literal) paragraph disables text formatting,
preserves spaces and line breaks, and is displayed in a
fixed-width font:

```plaintext
 This literal paragraph is indented with one space.
 As a consequence, *text formatting*, spaces,
 and lines breaks will be preserved.
```

Admonition paragraphs grab the reader's attention:

- `NOTE: This is a brief reference, please read the full documentation at https://asciidoctor.org/docs/.`
- `TIP: Lists can be indented. Leading whitespace is not significant.`

### Text Formatting

**Constrained (applied at word boundaries)**

```plaintext
*strong importance* (aka bold)
_stress emphasis_ (aka italic)
`monospaced` (aka typewriter text)
"`double`" and '`single`' typographic quotes
+passthrough text+ (substitutions disabled)
`+literal text+` (monospaced with substitutions disabled)
```

**Unconstrained (applied anywhere)**

```plaintext
**C**reate+**R**ead+**U**pdate+**D**elete
fan__freakin__tastic
``mono``culture
```

**Replacements**

```plaintext
A long time ago in a galaxy far, far away...
(C) 1976 Arty Artisan
I believe I shall--no, actually I won't.
```

**Macros**

```plaintext
// where c=specialchars, q=quotes, a=attributes, r=replacements, m=macros, p=post_replacements
The European icon:flag[role=blue] is blue & contains pass:[************] arranged in a icon:circle-o[role=yellow].
The pass:c[->] operator is often referred to as the stabby lambda.
Since `pass:[++]` has strong priority in AsciiDoc, you can rewrite pass:c,a,r[C++ => C{pp}].
// activate stem support by adding `:stem:` to the document header
stem:[sqrt(4) = 2]
```

### Attributes

**User-defined attributes**

```plaintext
// define attributes in the document header
:name: value
```

```plaintext
:url-gem: https://rubygems.org/gems/asciidoctor

You can download and install Asciidoctor {asciidoctor-version} from {url-gem}.
C{pp} is not required, only Ruby.
Use a leading backslash to output a word enclosed in curly braces, like \{name}.
```

**Environment attributes**

GitLab sets the following environment attributes:

| Attribute       | Description                                                                                                            |
| :-------------- | :--------------------------------------------------------------------------------------------------------------------- |
| `docname`       | Root name of the source document (no leading path or file extension).                                                  |
| `outfilesuffix` | File extension corresponding to the backend output (defaults to `.adoc` to make inter-document cross references work). |

### Links

```plaintext
https://example.org/page[A webpage]
link:../path/to/file.txt[A local file]
xref:document.adoc[A sibling document]
mailto:hello@example.org[Email to say hello!]
```

### Anchors

```plaintext
[[idname,reference text]]
// or written using normal block attributes as `[#idname,reftext=reference text]`
A paragraph (or any block) with an anchor (aka ID) and reftext.

See <<idname>> or <<idname,optional text of internal link>>.

xref:document.adoc#idname[Jumps to anchor in another document].

This paragraph has a footnote.footnote:[This is the text of the footnote.]
```

### Lists

#### Unordered

```plaintext
* level 1
** level 2
*** level 3
**** level 4
***** level 5
* back at level 1
+
Attach a block or paragraph to a list item using a list continuation (which you can enclose in an open block).

.Some Authors
[circle]
- Edgar Allen Poe
- Sheri S. Tepper
- Bill Bryson
```

#### Ordered

```plaintext
. Step 1
. Step 2
.. Step 2a
.. Step 2b
. Step 3

.Remember your Roman numerals?
[upperroman]
. is one
. is two
. is three
```

#### Checklist

```plaintext
* [x] checked
* [ ] not checked
```

<!-- vale gitlab.Spelling = NO -->

#### Callout

<!-- vale gitlab.Spelling = YES -->

```plaintext
// enable callout bubbles by adding `:icons: font` to the document header
[,ruby]
----
puts 'Hello, World!' # <1>
----
<1> Prints `Hello, World!` to the console.
```

#### Description

```plaintext
first term:: description of first term
second term::
description of second term
```

### Document Structure

#### Header

```plaintext
= Document Title
Author Name <author@example.org>
v1.0, 2019-01-01
```

#### Sections

```plaintext
= Document Title (Level 0)
== Level 1
=== Level 2
==== Level 3
===== Level 4
====== Level 5
== Back at Level 1
```

#### Includes

NOTE:
[Wiki pages](project/wiki/index.md#create-a-new-wiki-page) created with the AsciiDoc
format are saved with the file extension `.asciidoc`. When working with AsciiDoc wiki
pages, change the filename from `.adoc` to `.asciidoc`.

```plaintext
include::basics.adoc[]
```

To guarantee good system performance and prevent malicious documents from causing
problems, GitLab enforces a maximum limit on the number of include directives
processed in any one document. You can include up to 32 documents, which is
inclusive of transitive dependencies.

To use includes from separate pages or external URLs, enable the `allow-uri-read`
in [application settings](../administration/wikis/index.md#allow-uri-includes-for-asciidoc).

```plaintext
// define application setting allow-uri-read to true to allow content to be read from URI
include::https://example.org/installation.adoc[]
```

### Blocks

```plaintext
--
open - a general-purpose content wrapper; useful for enclosing content to attach to a list item
--
```

```plaintext
// recognized types include CAUTION, IMPORTANT, NOTE, TIP, and WARNING
// enable admonition icons by setting `:icons: font` in the document header
[NOTE]
====
admonition - a notice for the reader, ranging in severity from a tip to an alert
====
```

```plaintext
====
example - a demonstration of the concept being documented
====
```

```plaintext
.Toggle Me
[%collapsible]
====
collapsible - these details are revealed by clicking the title
====
```

```plaintext
****
sidebar - auxiliary content that can be read independently of the main content
****
```

```plaintext
....
literal - an exhibit that features program output
....
```

```plaintext
----
listing - an exhibit that features program input, source code, or the contents of a file
----
```

```plaintext
[,language]
----
source - a listing that is embellished with (colorized) syntax highlighting
----
```

````plaintext
\```language
fenced code - a shorthand syntax for the source block
\```
````

```plaintext
[,attribution,citetitle]
____
quote - a quotation or excerpt; attribution with title of source are optional
____
```

```plaintext
[verse,attribution,citetitle]
____
verse - a literary excerpt, often a poem; attribution with title of source are optional
____
```

```plaintext
++++
pass - content passed directly to the output document; often raw HTML
++++
```

```plaintext
// activate stem support by adding `:stem:` to the document header
[stem]
++++
x = y^2
++++
```

```plaintext
////
comment - content which is not included in the output document
////
```

### Tables

```plaintext
.Table Attributes
[cols=>1h;2d,width=50%,frame=topbot]
|===
| Attribute Name | Values

| options
| header,footer,autowidth

| cols
| colspec[;colspec;...]

| grid
| all \| cols \| rows \| none

| frame
| all \| sides \| topbot \| none

| stripes
| all \| even \| odd \| none

| width
| (0%..100%)

| format
| psv {vbar} csv {vbar} dsv
|===
```

### Colors

It's possible to have color written in `HEX`, `RGB`, or `HSL` format rendered with a color indicator.
Supported formats (named colors are not supported):

- `HEX`: `` `#RGB[A]` `` or `` `#RRGGBB[AA]` ``
- `RGB`: `` `RGB[A](R, G, B[, A])` ``
- `HSL`: `` `HSL[A](H, S, L[, A])` ``

Color written inside backticks is followed by a color "chip":

```plaintext
- `#F00`
- `#F00A`
- `#FF0000`
- `#FF0000AA`
- `RGB(0,255,0)`
- `RGB(0%,100%,0%)`
- `RGBA(0,255,0,0.3)`
- `HSL(540,70%,50%)`
- `HSLA(540,70%,50%,0.3)`
```

### Equations and Formulas (STEM)

If you need to include Science, Technology, Engineering and Math (STEM)
expressions, set the `stem` attribute in the document's header to `latexmath`.
Equations and formulas are rendered using [KaTeX](https://katex.org/):

```plaintext
:stem: latexmath

latexmath:[C = \alpha + \beta Y^{\gamma} + \epsilon]

[stem]
++++
sqrt(4) = 2
++++

A matrix can be written as stem:[[[a,b\],[c,d\]\]((n),(k))].
```

### Diagrams and flowcharts

It's possible to generate diagrams and flowcharts from text in GitLab using
[Mermaid](https://mermaidjs.github.io/) or [PlantUML](https://plantuml.com).

#### Mermaid

> [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/31818) in GitLab 13.3.

Visit the [official page](https://mermaidjs.github.io/) for more details.
If you're new to using Mermaid or need help identifying issues in your Mermaid code,
the [Mermaid Live Editor](https://mermaid-js.github.io/mermaid-live-editor/) is a helpful tool
for creating and resolving issues within Mermaid diagrams.

To generate a diagram or flowchart, enter your text in a `mermaid` block:

```plaintext
[mermaid]
----
graph LR
    A[Square Rect] -- Link text --> B((Circle))
    A --> C(Round Rect)
    B --> D{Rhombus}
    C --> D
----
```

#### Kroki

Kroki supports more than a dozen diagram libraries.
To make Kroki available in GitLab, a GitLab administrator needs to enable it first.
Read more in the [Kroki integration](../administration/integration/kroki.md) page.

After Kroki is enabled, you can create diagrams in AsciiDoc and Markdown documents.
Here's an example using a GraphViz diagram:

**AsciiDoc**

```plaintext
[graphviz]
....
digraph G {
  Hello->World
}
....
```

**Markdown**

````markdown
```graphviz
digraph G {
  Hello->World
}
```
````

#### PlantUML

PlantUML integration is enabled on GitLab.com. To make PlantUML available in self-managed
installation of GitLab, a GitLab administrator [must enable it](../administration/integration/plantuml.md).

After PlantUML is enabled, enter your text in a `plantuml` block:

```plaintext
[plantuml]
----
Bob -> Alice : hello
----
```

### Multimedia

```plaintext
image::screenshot.png[block image,800,450]

Press image:reload.svg[reload,16,opts=interactive] to reload the page.

video::movie.mp4[width=640,start=60,end=140,options=autoplay]
```

GitLab does not support embedding YouTube and Vimeo videos in AsciiDoc content.
Use a standard AsciiDoc link:

```plaintext
https://www.youtube.com/watch?v=BlaZ65-b7y0[Link text for the video]
```

### Breaks

```plaintext
// thematic break (aka horizontal rule)
---
```

```plaintext
// page break
<<<
```
